X-Git-Url: http://git.rot13.org/?a=blobdiff_plain;f=include%2Flinux%2Ffile.h;h=74183e6f7f458052c72d0bf3e8297c83a32ff18c;hb=6b8cc71ab2619a776b02869fd733ac1ead3db4e8;hp=418b6101b59a02d8b9efb7501e3de51808a59f95;hpb=70ac551651a2c5a234b703d9a495817f2ca09639;p=powerpc.git diff --git a/include/linux/file.h b/include/linux/file.h index 418b6101b5..74183e6f7f 100644 --- a/include/linux/file.h +++ b/include/linux/file.h @@ -10,6 +10,7 @@ #include #include #include +#include /* * The default fd array needs to be at least BITS_PER_LONG, @@ -17,10 +18,22 @@ */ #define NR_OPEN_DEFAULT BITS_PER_LONG +/* + * The embedded_fd_set is a small fd_set, + * suitable for most tasks (which open <= BITS_PER_LONG files) + */ +struct embedded_fd_set { + unsigned long fds_bits[1]; +}; + +/* + * More than this number of fds: we use a separately allocated fd_set + */ +#define EMBEDDED_FD_SET_SIZE (BITS_PER_BYTE * sizeof(struct embedded_fd_set)) + struct fdtable { unsigned int max_fds; int max_fdset; - int next_fd; struct file ** fd; /* current fd array */ fd_set *close_on_exec; fd_set *open_fds; @@ -33,13 +46,20 @@ struct fdtable { * Open file table structure */ struct files_struct { + /* + * read mostly part + */ atomic_t count; struct fdtable *fdt; struct fdtable fdtab; - fd_set close_on_exec_init; - fd_set open_fds_init; + /* + * written part on a separate cache line in SMP + */ + spinlock_t file_lock ____cacheline_aligned_in_smp; + int next_fd; + struct embedded_fd_set close_on_exec_init; + struct embedded_fd_set open_fds_init; struct file * fd_array[NR_OPEN_DEFAULT]; - spinlock_t file_lock; /* Protects concurrent writers. Nests inside tsk->alloc_lock */ }; #define files_fdtable(files) (rcu_dereference((files)->fdt)) @@ -60,8 +80,6 @@ extern void put_filp(struct file *); extern int get_unused_fd(void); extern void FASTCALL(put_unused_fd(unsigned int fd)); struct kmem_cache; -extern void filp_ctor(void * objp, struct kmem_cache *cachep, unsigned long cflags); -extern void filp_dtor(void * objp, struct kmem_cache *cachep, unsigned long dflags); extern struct file ** alloc_fd_array(int); extern void free_fd_array(struct file **, int); @@ -94,5 +112,6 @@ struct task_struct; struct files_struct *get_files_struct(struct task_struct *); void FASTCALL(put_files_struct(struct files_struct *fs)); +void reset_files_struct(struct task_struct *, struct files_struct *); #endif /* __LINUX_FILE_H */